Boundary systems are commonly used in conjunction with staircases, ramps, or the like to prevent people from falling over the edge of these structures. Integral to such boundary systems are rail members parallel to the edge of the staircase or ramp, commonly known in the art as handrails or banisters. Such handrails or banisters may be anchored to a fixed substantially vertical surface, for example a wall or a newel post, via a butt joint of a terminal end of the handrail or banister. Such butt joints are typically formed with fasteners that connect a handrail or banister to a wall or other vertical surface.
Examples of boundary systems may be appreciated from U.S. Pat. Nos. 5,437,433 and 4,928,930, and from U.S. Patent Publication No. 2007/0246698. Such systems may include a series of vertical support members that extend from the railing to a base. Each support may have a connector or connectors that allow the installer to adjust the angle between the support and the railing so the support members engage the handrail or banister at a desired pitch angle. Such connectors are not useful for connecting end portions of a handrail or banister to a vertical surface. Instead, those connectors are configured to support the handrail or banister and to provide a connection between the handrail or banister and lower support members, such as balusters or posts.
U.S. Pat. No. 4,150,907 teaches the use of a stanchion connector assembly adapted to provide an anchor for the terminal end of a handrail or banister. The stanchion connector assembly is configured to be secured to a stanchion at a series of angles defined by a slot formed in a portion of the connector assembly. This slot extends vertically and is configured to receive a screw for fastening an end of a handrail or banister to the stanchion at any number of positions defined by the vertically extending slot.
The amount of adjustment possible in the apparatus disclosed in U.S. Pat. No. 4,150,907 is thus limited by the length of the slot. Rotation of the handrail or banister against the anchor is only possible to the extent that the slot remains aligned with an aperture for receiving a fastener. The adjustability provided by the slot is only provided along one axis.
The pitch angle of the rail is adjustable within the physical constraints of the anchor and the slot, but no side-to-side rotation, commonly referred to as the yaw angle, is possible. Furthermore, it is not possible to rotate the apparatus around the aperture in the anchor, commonly referred to as the roll angle. As such, it is not possible to securely fasten the rail member at any yaw angle without the use of shims or cutting into the surface to which the connector is attached. If the mounting surface is warped or curved or irregular the installer may spend considerable time cutting the mounting surface or installing shims to obtain a secure joint with a conventional connector. Furthermore, a person who has limited carpentry skills may never be able to create a secure joint in these situations.
Railing systems currently available in the market are sold with connectors that are pre-configured at the time of manufacture to the particular pitch angle, yaw angle, and roll angle required, or a connector that is adjustable with respect to the pitch angle only. These connectors are useful in most installations because the railing is not being attached to a curved or warped surface. Should the installer encounter a curved or warped surface or be required to mount the rail at a non-standard angle, the installer must make an on-site adaptation of the mounting surface or the connector or both to make a secure joint. This is inconvenient and increase the time required to install the railing. Furthermore, such adaptation of the fixed substantially vertical surface or of the connector may be beyond the purview of person with limited carpentry skills such as a “do-it-yourself” homeowner.
A new connector for effecting a butt joint between a rail member and a fixed substantially vertical surface is needed which provides for the adjustment of the pitch angle, the yaw angle, and the roll angle in a manner easy enough to be employed by a homeowner or other person unskilled in carpentry or the like.